Rotary machine



g. 18, 1953 N. N. sTRATvElT ROTARY MACHINE Filed Dec. 30, 1947 2Sheets-Sheet 1 .All

Aug. 18, 1953 N. N. sTRATvElT 2,649,053

Y ROTARY MACHINE Filed Deo. 3o, 1947 2 sheets-shea 2 Patented Aug. 18,1953 ROTARY MACHINE Nils Nilsen '.Strtveit, Oslo, No1-'way ApplicationDecember 30, 1947, vSerial.No.-'794,556 In NorwayOctober 14, 1943Section 1, Public Law 690;August'8, 19146 Patentexpires October 14, 1963The present invention relates to rotary machines of the type having apiston that operates within a closed space formed between a wall outsideof and a wall inside of the piston, and which machines also have organsgoverning the movements of the piston, for instance in such manner thatall points on the piston describe a circular orbit of equal radii.

In the following description it is supposed that the pistonisof'annular'shape and operates with.- in a space between an inner and anouter cylindric wall, and that the piston is connected with a crank onthe machine shait by means of a' plane disc, that is situated at rightangles'to themachine shaft, between the endl surfaces ofthe piston, andextends through an'annular slot in the inner and -in the outercylindric'walls. However, the invention is not limited'tosuch embodimentthereof.

The present invention more specifically refers to the construction andarrangement oftheV organs governing the piston movements, but alsoincludes some other features in connection there'- with.

Different arrangements for governing therpiston movements in machines ofthel specified type have been suggested, but all-of them have one ormore drawbacks, and it is the object of the pres'- ent invention toprovide a governing arrange-Y ment that avoids such drawbacks.

In order to make the invention more clearly understood, there are shownin the accompanying drawings, means for carrying the same into practicaluse, without limiting the improvementsin their useful application to theparticularconstructions illustrated forthe purpose of explanation.

In the drawings:

Fig. 1 is a diagrammatical View 'of an embodiment of a machine accordingto the invention,

partly in section, said section being taken on-line I--I in Figure 2.

Fig. 2 shows a section taken on line'II-II in Figure 1.

Figs. 3, 4 and 5 diagrammatically illustrate. different governingmechanisms.

Fig. 6 is a diagrammatical section corresponding to Figure 2 but showinga second embodiment.

of the invention, and

Fig. '7 is a similar section showing a third vembodiment of theinvention,

Fig. 8 is a corresponding side view of Fig. '7, and

Fig. 9 shows a detail.

The rotary Amachine shown in Figures 1 and 2 comprises a-housingconsisting of two plane end walls 2 and 3 and of two `concentriccylinder walls i and 5 provided between the end walls. Between thetwofcylindrical walls is formedan annularspace 6.

In theouter cylinder wall, adjacent to each other, there are providedtwo openings l and 8, leading to the suction side and to the pressureside respectively of the machine (in case the machine isused as pump oras compressor) or to outlet and to inlet conduits respectively (if themachine is used as `a, motor). Between the openings 'i and 8 is aradal'partition 9 extending entirely xover the space between thecylindrical walls- 4 .and .5.

The annular space 6 receives the piston l. This piston also annular, buthas a relatively broad'axial slot at thelocaton of partition 9. Thisslot enables movements of the piston without being hindered bysaidpartition.

Numeral ilv designates a plane disc which in the embodiment shownisplaced midway between the .end walls 2 and '3. Disc Il extends throughthe piston and is rigidly secured thereto. Further, discllextendsthrough annular slots I5 and l'providedin the inner and in the outercylindric wa'lls4 respectively. Slot I6 is closed along thecircumference, so that'a` closed annular chamber His formed.

Within the inner cylinder formed by inner cylindrical Wall ilV the discll is supported, through ball bearings I8, onthe crank pin I9 of thedriving'shaftZ. The latter is support-ed by ball bearings 2 land '22.

In ord-erto' provide a piston movement in which all points of the pistonmove in circular orbits of equal dia-meters a Vlink lever'system -orylevers comprising lever'members orlinks 23, 24, 25, 26, 2? is providedwithin the cylinder d. Links or levers 23, 24 are pivotable on studs 28,29 rigidly secured to the cylinder 4, and the other ends Sil, 3l of saidlinks vor levers are pivo-tally connected to the meinber- 25. Links orleversy 26, 2l are linked to the disc Il at 32, 33 and to the member 25at 34 and A35 respectively.

I-n this embodiment, in which the control members-are situated withinthe inner cylindrical wall Il,v all bearings andl connections needinglubrication may be lubricated in a very simple manner, since thespace'inside `of the wall i may beclosed and'used'as 'anoil container.During operation of the machine, the oil in saidv container is whirledup, say b y means of balancing weightsiprovided o n the shaft 2li. Thusthe bearing I8-of crank l-S, the' bearings 2l and 22 of the mach-ineshaft 25B and-the several link connections 28, 29 etc. are continuouslyand effectivelylubrcated.

In this embodiment of the machine it is as a rule desirable to preventleakage of gas from the operation chamber t into the space inside of thecylindrical wall 4i. For this purpose slot I5, through which extendsdisc l! suitably, suitably so arranged that gas leaking from the outsideof the cylindrical wall 4 to the inner side thereof must first passthrough a chamber 35, from which the gas may be extracted, for instanceby the chamber communicating with the atmosphere. At the saine timetightening organs 31, 38, preferably resilient and adjustable, may beprovided on the parts stationary within said slot.

When a parallel-system Vof links or levers is used for governing thepiston, it is possible that said system is non-symmetrical and has itslinks directed inwards, which is the case of Figure l.

For an explanation of what is meant by a nonsymmetrical system the linksof which extend inwards, reference is made to the diagrammatical Figures3, 4 and 5.

On Figure 3 a-a is the link couple the ends of which are pivotallyconnected to stationary parts, for instance to the inner cylindricalwall 4. Links a-o thus correspond to links 23, 2d on Figure l.

b-b designate the other link couple, and correspond to links 23, 2l onFigure l. c isa central organ or common member (member 25 on Figure 1)with which both link couples are connected at points A-A and BBrespectively.

Point S, in which intersect lines interconnecting points A A and pointsB-B respectively coincides with the central point of each of theselines. rThis means that the linkage of Figure 3 is symmetrical. Here itis irrelevant whether links a-d are directed towards the right as shown,or towards the left, or whether links b-b are directed downwards, asshown, or upwards.

Figure 4 shows a non-symmetrical link system. The same letterdesignations are used as in Figure 3, only with the difference that theletters are indexed. In Figure i the point of intersection S of linesA'-A and B-B does not coincide with the center point lVIA of line A-Anor with the center point MB of line B-B. Further it is seen that linksc-c' extend toward that side of line AA on which the central point MB islocated, and that links b'-b extend toward that side of line B'-B onwhich the central point MA is located. IThis means that the links aredirected inwards. The link system of Figure 4 corresponds to that ofFigure l.

Figure 5 illustrates a non-symmetrical link system in which the linksare extending outwards..

A iull explanation of this gure is deemed unnecessary in View of thatalready given in connection with Figure 4.

As above mentioned a link system according to the invention suitably isnon-symmetrical and has its links directed inwards. However, asemisymmetrical link system the links of which extend inwards may beused. semi-symmetrical link system is a system in which the intersectionof the two connection lines A-A and B-B coincides with the central pointof one of said lines, but not with that of the other line. In suchsemisymmetrical arrangement the links corresponding to that connectionline the midpoint of which coincides with said point of intersection,should be directed towards that side of the companion connection line onwhich the mid-point of the other connection line is located. The othertwo links may extend in either direction, at will.

If an entirely non-symmetrical link system is used the central organ cshould, in accordance with the invention, be so constructed thatvibrations due to mass forces are reduced to a minimum. This may beachieved by distributing the masses of the central organ C (and ofmembers rigidly connected with C) in such manner that the direction ofthe resultant of the mass force from C' (and from members rigidlyconnected with C) and the mass force transmitted from C to those links(o'e-a) the other ends of which are :attached to stationary members,entirely or approximately Vgoes through the mid-point (MB) of theconnection line (B-B) between the attachment points on organ C of thoselinks (IY-lf) the other ends of which are secured to the piston.

According to the invention the governing organs also may be situatedoutside of the outer cylindrical wall 5, if desired. Such .anarrangement is shown on Figure 6. In this figure the numerals 2, 3, 4,5, lil, Il and 2li refers to parts corresponding to those having similarnumerals in Figures l and 2. Outside of the outer cylindrical wall 5there is provided a crank pin 46 extending through a bearing il providedin the disc. The shaft 42 of said crank pin is driven by a gear t3meshing with a gear i9 and the latter meshing with a gear 45; secured tothe machine shaft 29 so that shaft l2 is driven in synchronism withshaft 25). Thus a positive governing of crank pin d@ is obtained.

Figures 7 and 8 disclose a denite arrangement in which the governingorgans of the piston are located outside of the outer cylindrical wall,but where said governing organs do not have positive drive directly fromthe machine shaft. In these figures numerals 2, 3, B, 5, I, il and 2Scorrespond to similarly numbered parts in Figures l and 2. According toFigures 'i' and 8 three crank pins 45, received in bearings 45, aredistributed at equal distances between them around the circumference ofdisc Il. In this embodiment the crank shafts il are free to rotate andare not driven from the machine shaft 20.

In those embodiments where the governing organs of the piston arelocated outside of the outer cylindrical wall, and where between thepiston ends there is provided a radial disc extending through said outercylindrical wall, it will be suitable that that space into which thedisc extends outside of said wall is a closed space, in which thegoverning organs are located. In such case it may be of importance toprevent leakage of gas from the operation chamber into said closed spaceoutside of the outer cylindrical wall. For this purpose it is suitableto so construct the slot in the outer cylindrical wall, through whichslot the disc extends, that gas that leaks out must-prior to enteringthe closed space in which the governing organs are located-pass achamber from which such gas may be drained,

for instance by said chamber being in communication with the atmosphere.Thus leakage gas will not at all enter the closed space where thegoverning organs or the bearings are located.I

tightening organs to the stationary parts, as

shown.

.remote I claim:

'1. A rotary .machine .comprising a closed casing with inlet and outletopenings, said casing having a working space limited vby spacedconcentric cylinder walls, partition means between said inlet and outletopenings in said lworking space separating the outlet side of theworking space from the inlet side thereof, ai piston adapted to operatein the said casing between the said cylinder walls, said piston beingslotted for movement about said partition means, a drive shaft rotatablyjournalled in said casing, means adapted to transmit the workingmovements oi the said piston, said means connecting said piston to saiddrive-shaft, controlling means adapted to govern the movements of saidpiston being connected to the said casing and the said piston, and beingpositioned outside the said working space, and inside the innermostsurface 0f the Working space.

2. A rotary machine comprising a casing, spaced concentric cylinderwalls in said casing dening a cylindrical closed working spacetherebetween and said casing, said casing having inlet and outletopenings therein for said closed space, a drive shaft rotatablyjournalled in said casing, an annular piston in said closed space,partition means in said closed working space between said inlet andoutlet openings dividing said space into low and high pressurecompartments, means eccentrically and movably connecting said driveshaft and said piston and adapted to transmit working movements of saidpiston, controlling means connected to said casing and said piston forgoverning the movements of said piston in said cylindrical workingspace, said piston being slotted for movement about said partitionmeans, said controlling means being positioned outside said workingspace and inside the innermost surface of said working space.

3. A rotary machine comprising a casing, said casing being formed of twospaced concentric cylinders and end walls to form a closed working spacebetween said concentric cylinders, said casing having inlet and outletopenings to said working space, a cylindrical piston in said closedspace, partition means in said working space between said inlet andoutlet openings dividing said space into low and high pressure chambers,a disc rigidly attached to said piston and extending through the innerof said concentric cylinders, said piston being slotted for movementabout said partition means, lever members operatively connected to saiddisc for governing the movements of said piston, a drive shaftrotatably7 journalled in said casing externally of said working space, acrank end eccentrically mounted on said drive shaft, said disc beingsupported on said crank end, said lever members constituting a linkmechanism for governing the movements of said piston whereby all pointsof the piston move in circular orbits of equal radii, said lever membersbeing located externally of the working space and inside the innermostof said concentric cylinders adjacent said drive shaft.

4. A rotary machine as claimed in claim 3, means dening a gas trapchamber on the inner of said concentric cylinders extending peripherallyaround the innermost surface thereof outside the working space, saiddisc connected to said piston passing through said gas trap chamber insealing relation therewith and said gas trap chamber being incommunication with the atmosphere whereby gas leaking from the Work- 6ing vspace towards the space containingthegoverning organs `can beexhausted.

5. A rotary machine comprising a casing, said casing comprising spacedconcentric cylinder walls, end walls on said casing, said concentriccylinder walls 'and said end `wallsdeninjg therebetween an'annularworking chamber, :said casing having inlet A'and 'outletvopenings to said working space, partition means in said working spacebetween said openings dividing said space into low and high pressurecompartments, an annular piston in said chamber, said piston beingslotted for movement about said partition means, the inner of saidcylinder walls having an annular slot therethrough, a disc rigidlysecured to said piston and extending inwardly through said annular slot,a drive shaft rotatably journalled in said casing, said disc beingeccentrically mounted on said shaft, a lever system operativelyconnected to said disc and to said casing for controlling the movementsof said piston, said lever system being located internally of the innersurface of the innermost one of said concentric cylinder walls andexternally of the working space.

6. A rotary machine as claimed in claim 2, in which the controllingmeans comprises two pairs of links, the ends of one link pair beingpivoted on stationary parts of said machine, a member common to eachsaid link pair, the other ends of said one link pair being linked tosaid member common to each said link pair, the ends of the second linkpair being pivoted on the piston, the other ends of said second linkpair being linked to said common member, and where the intersection of aline interconnecting those points on the common member at which theiirst mentioned link pair is pivoted and of a line interconnecting thosepoints on the common member at which the second mentioned link pair ispivoted, does not coincide with the mid-point of any of saidinterconnecting lines, and the links of each pair are directed towardsthat side of the interconnecting line of each pair on which is locatedthe mid-point of the interconnecting line of the other link pair.

7. A rotary machine as claimed in claim 2, in which the controllingmeans comprises two pairs of links, the ends of one link pair beingpivoted on stationary parts of said machine, a member common to eachsaid link pair, the other ends of said one link pair being linked tosaid member common to each link pair, the ends of the second link pairbeing pivoted on the piston, the other ends of said second link pairbeing linked to said common member and where the intersection of a lineinterconnecting those points on the common member at which the rstmentioned link pair is pivoted and of a line interconnecting thosepoints on the common member at which the second mentioned link pair ispivoted, does not coincide with the mid-point of any of saidinterconnecting lines, the mass of said common member, and of membersrigidly secured thereto, being so distributed that the direction of theresultant of the mass force from said common member and of the massforce transmitted from those links the other ends of which are attachedto said stationary parts of the machine, extends substantially throughthe mid-point of a line interconnecting the attachment points on thecommon member of those links the other ends of which are attached to thepiston.

NILs NILsEN sTRTvEIT.

(References on following page) References Cited in the le of this patentUNITED STTES PATENTS Number Name Date Winkler Oct. 30, 1877 Allyn July10, 1888 Varley May 17, 1921 Varley Nov. 10, 1925 Number 5 Number NameDate Williams Aug. 7, 1928 FOREIGN PATENTS Country Date Switzerland May1, 1941 France 1907 France Apr.` 2, 1921

